This study is the first phase of a larger proposal. Phase I, under the direction of Dr Paneth, will study four large, population-based, very low birthweight cohorts with follow-up to school age. The earliest cohort is from Ontario, overseen by Dr Saigal, a second from Holland is overseen by Dr Verloove, a third from New Jersey is overseen by Dr Paneth, and a fourth from Bavaria, Germany, is overseen by Dr Wolke. The cohorts represent varying patterns of NICU treatment. Phase I aims to 1) describe and estimate current school age health and developmental outcomes of infants cared for in newborn intensive care units and 2) obtain a common multi-attribute health status assessment (using a common scoring system) on adolescent survivors not already surveyed, to describe functional status and 3) develop an assessment system for neonatal management approaches to care in the various cohorts and 4) assess the relationship, if any, between management approaches and survival in addition to short and long-term outcomes.